Air Fryer Blooming Onion Petals

Ingredients

• 45 ml (3 tbsp)mayonnaise
• 45 ml (3 tbsp)ketchup
• 1.25 ml (¼ tsp)Worcestershire sauce
• 2.5 ml (½ tsp)horseradish
• 0.6 ml (⅛ tsp)paprika
• 0.6 ml (⅛ tsp)garlic powder
• 0.6 ml (⅛ tsp)onion powder
• 0.6 ml (⅛ tsp)dried oregano
• 1.25 ml (¼ tsp)salt
• ⅛ tsppepper
• 1 largeonion
• 1egg
• 15 ml (1 tbsp)milk
• 125 g (1 cup)plain flour
• 5 ml (1 tsp)salt
• ½ tsppepper
• 1.25 ml (¼ tsp)cayenne pepper
• 2.5 ml (½ tsp)paprika
• 2.5 ml (½ tsp)garlic powder
• 2.5 ml (½ tsp)onion powder
• 2.5 ml (½ tsp)baking powder
• as neededoil spray

Instructions

1. 1

   Mix the sauce

   Stir the mayonnaise, ketchup, Worcestershire sauce, horseradish, paprika, garlic powder, onion powder, oregano, salt and pepper together in a small bowl. Cover and refrigerate.

2. 2

   Cut the onion

   Preheat the air fryer to 175°C (350°F). Halve the onion through the root, keeping the root end attached at first. Cut each half into 3 wedges, remove the root end, then separate the wedges into petals and set them aside.

3. 3

   Coat the petals

   Beat the egg and milk in a small bowl. Put the flour, salt, pepper, cayenne, paprika, garlic powder, onion powder and baking powder in a large resealable bag and shake to combine. Add the onion petals, seal the bag and shake to coat. Shake off excess flour, dip the petals in the egg mixture, then return them to the flour bag and shake again. Arrange the coated petals in the air fryer.

4. 4

   Air-fry the onion

   Spray the petals generously with oil so no dry flour is visible. Cook at 175°C (350°F) for 5 minutes, turn the petals, spray again and cook for another 5 minutes. Turn them once more and cook for a final 5 minutes. Serve with the sauce.

What are blooming onion petals?

A blooming onion is a restaurant-style appetiser made by cutting an onion into sections, coating it in seasoned batter and frying it with the pieces opening out like a flower. This version separates the onion into petals before cooking, so each piece can be coated and picked up individually.

The air fryer gives the coating a crisp finish with less oil than deep-frying, while a tangy, creamy dipping sauce keeps the familiar appetiser feel.

Nutrition and macros by portion

The nutrition label shows one serving as written: 470 calories, 10g protein, 61g carbs, 19g fat.

The flour and onion provide most of the carbohydrates, while mayonnaise and the oil spray contribute much of the fat. The egg and flour provide some protein, though this is still an appetiser rather than a protein-focused meal. Serve a portion with a salad or vegetables to balance the plate.

Why cut the onion into petals?

Root end: Keeping it attached while you first cut the onion helps hold the halves together as you make the wedges. Remove it afterwards so the wedges can be separated into petals.

Even pieces: Separate the petals before coating so flour and egg can reach their surfaces. Smaller petals may cook faster, so check them as they finish.

Getting the coating to stick

Two-stage coating: Shake the petals in the seasoned flour, dip them in the beaten egg and milk, then return them to the flour. Shake off excess flour at each stage to avoid a thick, patchy shell.

Oil spray: Coat all visible flour before cooking and again after turning. Dry flour can remain pale and powdery rather than crisping.

Air-fryer timing and texture

Cooking sequence: The petals cook at 175°C (350°F) for 5 minutes, then another 5 minutes after turning, followed by a final 5 minutes after a second turn.

Doneness: Look for a browned, crisp coating and tender onion. If pieces vary in size, remove the smaller ones when ready and give larger petals a little more time.

The dipping sauce

Chilling: Mix the sauce before preparing the onion and refrigerate it while the petals cook. This gives the flavours time to mingle and keeps the dip cool for serving.

Balance: Ketchup brings sweetness and tang, while horseradish and Worcestershire sauce add savoury sharpness. Stir the sauce again before serving.

Serving ideas

Serve the petals hot with the chilled sauce on the side, so the crisp coating does not soften while waiting. They work well as a shared appetiser or snack.

For a more substantial plate, pair them with a fresh salad or crunchy vegetables. These add contrast to the rich dip and crisp coating.

Recipe notes & tips

• Keep the onion root attached until the wedges are cut to help the halves stay together.
• Shake off extra flour before dipping the petals in the egg mixture.
• Arrange the petals with space between them so the air fryer can circulate hot air.
• Spray away all visible dry flour before cooking and after turning.
• Turn the petals carefully so the coating stays in place.

Variations

• Smoky paprika: Replace some of the paprika with smoked paprika for a deeper flavour.
• Extra heat: Add a little more cayenne to the flour mixture for a spicier coating.
• Herb seasoning: Add dried thyme to the flour mixture alongside the oregano.
• Tangier dip: Stir a little extra horseradish into the sauce before serving.
• Dairy-free coating: Use an unsweetened plant-based milk in place of the milk.

Common mistakes to avoid

• Leaving dry flour: Spray the petals until no floury patches are visible before cooking.
• Crowding the basket: Cook in batches if needed so the petals can crisp rather than steam.
• Skipping the turns: Turn the petals at both 5-minute intervals for more even cooking.
• Using large uneven pieces: Separate the wedges into petals so they cook more consistently.
• Overcoating: Shake off loose flour before the egg dip and again before air-frying.

How to store

Refrigerate leftover petals in an airtight container for up to 3 days, storing the sauce separately. Reheat the petals in the air fryer until hot and crisp; the coating may soften during storage.

Frequently asked questions